The “Expand-A-Lung”Breathing Exerciser is the #1 choice of competitive athletes, to increase lung capacity and endurance. It is a breathing exercise that provides breathing resistance as you inhale and exhale through the comfortable mouthpiece that’s attached to the small, 100% adjustable air-flow valve.

This is the ideal breathing trainer that focuses on providing the only inspiratory/expiratory lung exercise available in the most compact, simple and durable lung exerciser in the market.